White balance control device and method

Abstract

The invention relates to a white balance control device and a method thereof, which can improve white detecting accuracy under the lower color temperature light source and implement stable white balance control even the light source incapable of white detecting. The method comprises following steps: S1 achieving an estimate evaluation by a block unit; S2 detecting a white detecting block in a first detecting range from the estimate evaluation; S3 entering into S4 when the detected number is more than a certain standard, accumulating the estimate evaluation for each white detecting block, divided by the number of the white detecting blocks and calculating average estimate evaluation of each block; S6 R and B data of the whole picture multipled by WB augmenting factor R and B gain; enteringinto S7 when the detected number is less than a certain standard, determining whether under the lower color temperature light source according to the accumulated value of the whole blocks and the estimate evaluation of each block; entering into S4-S6 if under the lower color temperature light source by that the result in the second detection range multipled by WB augmenting factor.

Description

technical field [0001] The present invention relates to a control device for performing white balance provided in an image processing device, a control method thereof, and a computer-readable medium recording a control processing program. Background technique [0002] In the conventional white balance control, in order to detect the white subject part on the screen, a white detection range along the black body radiation curve representing the change of the white subject due to the change of the light source is set, and based on the white detection result extracted from the white detection range, Find the white balance correction coefficient. [0003] However, it is necessary to prepare for a wide white detection range from a high color temperature such as a shade or an incandescent lamp to a low color temperature side. Therefore, there is a possibility that a sunny face or a yellow flower may be misidentified as a low color temperature even under a high color temperature lig...

AI Technical Summary

Problems solved by technology

[0007] However, in this configuration, in order to obtain the white balance corresponding to the color temperature, it is necessary to first select the white detection range corresponding to the color temperature, or to infer the color temperature from the color, and the processing becomes complicated.

In addition, even if the low color temperature light source can be correctly discriminated, and there are various low color temperature light sources, if the white detection range on the low color temperature side is expanded without limit, there will be the following problem: Depending on the scene, the object that is not white will be discriminated against. Introducing white, even under the same light source, due to the problem of white balance deviation caused by the subject, the optimal white balance cannot be implemented for the light source where the original white detection cannot be performed.

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